Elastomers are used in applications as diverse as packer elements, blow out preventer elements, O-rings, gaskets, and the like. In downhole drilling and completion (for example gas and oilfield exploration and production, carbon dioxide sequestration, etc.) the elastomers are often exposed to high temperatures and harsh chemical and mechanical subterranean environments that can degrade elastomer performance over time, reducing their reliability. Thus, in the oil and gas industry, it is important for an elastomer to have good chemical resistance at high temperature. It is also desirable for the elastomer to have optimal mechanical strength so that it does not extrude during application and, when in use, an article made from the elastomer can hold differential hydraulic pressure while applied downhole.
Additives can be used to adjust the properties of the elastomers. One difficulty in developing suitable elastomeric materials for downhole applications is that use of one additive to improve one property can concomitantly degrade another desired property. For example, adding fillers to an elastomer can improve the mechanical strength of the elastomer. However, in order to achieve any meaningful improvement, fillers such as carbon black and nonporous silica have to be used in a significant amount; and at a high loading level, fillers can have detrimental effects on the elastomeric properties of the elastomer. To reduce the loading level of the filler, a binder may be used to bond the filler to the elastomer. However, this approach is more suitable for low temperature applications because at high temperatures, the bond between the filler and the elastomer provided by the binder tends to dissociate thus compromising the mechanical strength of the elastomeric material. In addition, binders tend to function as a plasticizer, which may lead to the deterioration of tensile properties of the elastomer.
Therefore, there remains a need in the art for elastomeric materials that provide a delicate balance of mechanical strength, elasticity, and chemical resistance at high temperatures. It would be a further advantage if the balance of the properties can be achieved at relatively low filler loading levels without using any binders.